Abstract:
The inventive gearbox device (200) comprises rotary members (1,2,4,5,15) provided with toothed elements (E2, E4-E7, S12, S34, S57-S7, D1-D3, DC, FC, F6, FR, ST), wherein at least one toothed gear (ST, E2, E4) for transmitting motion between two other rotary members (1, 5; 15, 4), thereby producing a gear ratio, can be selectively connected to a rotary member (4; 2) in order to produce another gear ratio.
Abstract:
For a first gear ratio, the flyweights engage the clutch and thus connect the input to the sun wheel, whilst the ring gear is immobilised by the free wheel. For the second gear ratio, the flyweights push the ring gear against the axial thrust of the helical teeth in a direction causing the engagement of the clutch against the ring and thus, at the same time, the disengagement of the clutch. The thrust produced by the teeth on the ring gear decreases and transmission then occurs from the input to the ring gear, whilst the sun wheel is immobilised by its free wheel. The speed increases further, the flyweights rise further, compress the prestressed springs and push the ring in the direction of the engagement of the clutch, which produces direct drive.
Abstract:
A multi-speed mechanical automatic transmission has two planetary gear trains, each including a sun gear, planet gears mounted in a planet carrier, and a ring gear. The first planetary gear train provides low gear and direct drive; the second train modifies low gear operation of the first train to provide an intermediate gear operation. The first sun gear is fixed to an input shaft, and the first planet carrier drives an output shaft. The second planet carrier is coupled to rotate the first ring gear in one direction, and free wheels or selectively actuated friction brakes prevent rotation of the first and second ring gears in the opposite direction. The first planetary train has helical gears, and a direct drive clutch selectively couples the first ring gear to the first planet carrier. This clutch is urged toward disengagement, so as to shift the transmission into low gear, by axial movement between the first ring gear and first planet gears in response to a driving torque applied between the gears; it is urged by centrifugal weights toward engagement so as to shift the transmission into direct drive. A second clutch selectively couples the second sun gear to the input shaft or, in the alternative, the second ring gear to the transmission housing. When the second clutch is disengaged, the second planetary train is idle and does not influence low gear operation of the first planetary train. When the second clutch is engaged, the second planetary train drives the first ring gear forward at a reduced speed to provide an overall ratio intermediate between low gear and direct drive.
Abstract:
The crown wheel of a planetary gear is connected to an input shaft while the planet carrier is connected to the output shaft. The sun wheel is locked by means of a free wheel when the clutch is released. The device then operates as a reduction gear. The sun wheel rotates with the crown wheel and the planer carrier when the clutch is engaged. The axial forces (F.sub.AP, F.sub.AC), sustained by the sun wheel and the crown wheel when in gear-reduction mode, and resulting from the helical tooth configuration, tend through the stop to compress a spring and release the clutch. When in direct drive and beyond a certain torque, the clutch slips, thereby generating the above-mentioned axial forces which compress the spring and accelerate disengaging. The device operates as a reduction gear until the torque on the shaft is reduced, thereby, enabling the spring to re-engage the clutch. For use on the input side of a gear box in order to automatically reduce speed ratios during acceleration, the gear box being itself preferably automatically controlled, especially under the effect of axial forces generated by other planetary gears.
Abstract:
The speed-responsive clutch has axle-free rocking flyweights which are rockingly mounted in correspondingly shaped recesses of a cage. The rocking movement of the flyweights corresponds to a substantially radial movement of the center of gravity of the flyweights and to a substantially axial movement of an actuator portion of the flyweights for variably pressing friction disks of the clutch.
Abstract:
A differential pinion shaft is coupled to the input shaft. A crown is coupled to the output shaft. The mechanical resistance of a compensated sub-assembly, multiplied by a gear, is transmitted to a planet wheel. The speed of rotation of the planet stabilizes and, as a result, the transmission ratio between the input shaft and the output shaft stabilizes when the two forces acting on the periphery of the pinion are equal, although they then correspond to a torque much larger on the output shaft than on the planet wheel, the couple on the planet wheel being greater than that on the shaft of the compensator sub-assembly. The sub-assembly comprises an inertial load and a consuming load the joint behavior of which, depending on the speed of rotation and on the acceleration, resembles, on a smaller scale, that of the vehicle.
Abstract:
The invention concerns a gearbox wherein the clutch shaft (3) selectively drives one or the other of two input shafts (1,2) by means of two clutches (8). The pinion torques defining the successive ratios are configured such that the power is alternately transmitted by one clutch (8) and by the other when the transmission ratios are made to succeed each other sequentially upon use of the gearbox. The input shafts (1,2) are non-coaxial and bear input pinions (E3, E4, E5, E6) which mesh with the same output pinions (S234, S56R). In an improved embodiment, one (1) of the input shafts drives an intermediate shaft (15) which in turn likewise drives the same output pinions (S234, S56R) via the input pinions (E4, E6) borne by said input shaft and operating this time as freely rotating motion transmitter pinions. The invention provides a compact device, and minimization of the number of pinions.
Abstract:
A device and a method of controlling a progressive change of an overall transmission ratio from an old transmission ratio to a new transmission ratio are described. The method is applicable in a transmission device comprising a first and a second gear trains which are independently shiftable for determining together an overall transmission ratio of the transmission device. The method includes detecting a physical magnitude which is influenced by progressive ratio change in the second gear train, resulting in a progressive variation of said overall transmission ratio in one direction, and also includes controlling an actuator of a first selective coupling means as a function of a detected value of the physical magnitude to progressively change a transmission ratio in the first gear train in a direction contrary to the first direction.
Abstract:
A transmission apparatus in which a differential-type transmission device has rotating elements with intermeshing teeth, one of which elements is connected to an input shaft and the other to an output shaft. One of the rotating elements is a reaction element, and the transmission apparatus has a selective locking mechanism mounted operatively between the reaction element and a housing of the transmission apparatus. The selective locking mechanism has a free-wheel for enabling the reaction element to rotate in the same direction as the input shaft and the output shaft when a selective connection device connects the rotating elements of said differential mechanism in order to cause direct drive operation. When the freewheel is locked, the reaction element is integral in rotation with a rotor of a brake which is able to be selectively released in order to release the rotor and the reaction element in relation to said housing. In a neutral condition the brake allows the reaction element to rotate in an opposite direction. The brake is furthermore able to be selectively and gradually activated so as to gradually immobilize the rotor in relation to the housing, whereby the reaction element is then selectively immobilized and allowed to rotate in the same direction as the input and output shafts.
Abstract:
A transmission device including a planetary gear train with a ring gear connected to the input, and a sun wheel counter-rotationally locked by a free-wheel. A planet carrier is connected to the output shaft. The ring gear and the planet pinion carrier my be coupled via a clutch which is compression-actuated by fly-weights to ensure direct drive. When the clutch is released by an axial thrust caused by the helical gearing and countering that of the fly-weights, the sun-wheel is immobilized by the free-wheel and the device operates as a reducing mechanism. The planetary gear train is arranged as an oil pump delivering through a duct and through the stack of clutch discs. When the clutch is actuated by the fly-weights, the delivery path is closed off, and the meshing motion between the gears forming the oil pump tends to be eliminated as a result. Therefore, the frictional process of the discs need only immobilize the gears to achieve direct drive. Ratio changes may be made more flexible, and clutch wear and heating may be reduced.